Car-brake.



PATENTED OCT. 17, 1905.

G. GREMM.

CAR BRAKE.

APPLICATION FILED JULY zz. 1905.

GEORGE GREMM, OF CHICAGO, ILLINOIS.

CAR-BRAKE.

Speccation of Letters Patent.

Patented Oct. 17, 1905.

Application filed July 22, 1905. Serial No. 270,807.

.the friction.

The main objects of my invention are to provide an improved form of cam for use in devices of this class, to provide for suitable adjustment to compensate for wear on the bear-l ingface of the cam, to provide improved mechanism for operating same, and to reduce the jar in the operation of said cam. I accomplish these objects by the device shown in the accompanying drawings, in which- Figure 1 is a longitudinal vertical section of a carto which a system of brakes constructed according to my invention has been applied. Fig. 2 is a transverse section along the line 2 2 of Fig. 1. Fig. 3 is an elevation, partly broken away, of a brake-cam such as is shown in position in Fig. 1. Fig. 4 is an end elevation of the same. Fig. 5 is a plan of the yielding connection between the operating-lever and the system of links for operating the cams. In the construction shown, 1 is the lower part of the brake mechanism of a car-body, which is normally supported by the Wheels 3. The rails below the car are represented at 4. The transverse shafts 5 are journaled in bearings 6, which are secured to the longitudinal beams 7 of the car-bod y 1. Each of the shafts 5 has keyed thereto a pair of brake-cams 8, each of which is disposed over one of the rails 4. An arm 9 is keyed to each of the shafts 5. These arms 9 are disposed in parallel relation and connected by links 10, which communicate through the link 11 with an operatinglever 12. The lever 12 is fulcrumed at 13 to a quadrant 14, which is secured upon one of the platforms of the car-body 1. The quadrant is provided in its periphery with notches 15, which engage a clutch-pin 16 on the lever 12. The clutch-pin 16 is released when the handles 17 and 18 are urged together, as by the grasp of the operators hand, as is usual in such devices. The lever 12 is secured to the link 11 by'means of a bolt 19, seated inra longitudinal slot 20 in the link 11, and is se cured to a block 21, slidably mounted on the link 11. The link 11 is provided with transversely-projecting lugs 22, and the block 21 is normally held in a central position between the lugs 22 by means of coiled springs 23. The rods 24 extend through apertures in the lugs 22 and serve as guides for the block 21..

The springs 23 4are also secured against lateral distortion by the rods 24` The cams 8 are preferably constructed as follows: The body-casting 25 has securely bolted at opposite sides of same two plates 26 and 27. The space between the plates 26 and 27 is entirely filled with material, as will be hereinafter described. The plate 27 being the plate toward the inside of the car is extended beyond the filling material and serves as a iiange 28 for guiding the cam upon the rail 4. The filling material at the ends of the cam 8 being the part which receives the most wear consists of the shoes 29, which are made of hard material. The shoes 29 are secured in position by bolts 30, which extend entirely through same and engage slots 31 in the plates 26 and 27. These slots 31 are disposed in the direction indicated, so that the shoe 29 may be adjusted in the direction of the arrow 32. Each of the shoes 29 is separated from the casting 25 by means of a backing-piece 33, which may be replaced or reinforced to increase its thickness to correspond with the adjustment of the shoe 29. The remaining space between the plates 26 and 27 is also filled with material, preferably wood, arranged in blocks 34, disposed so as to take the wear endwise of the grain. The periphery 35 of the plate 26 and the filling material of the cam 8 are so formed that when the cam 8 is thrown into engagement with the rail 4 the motion of the car will tend to increase the grip of said cam. Secured to the upper edge of the casting 25 of the cam 8 and at each side of the shaft 5 is a spring 36, which serves as a buffer to reduce the shock which occurs when the cams 8 are thrown into engagement with the rails 4. The springs 36 are secured in position by means of bolts 37, tapped into the castings 25 at the lower end of said spring. Buffer-blocks 38 are rigidly secured to the car-body 1 in suitable position to engage the springs 36 when the cams are in their operative position.

The operation of the device shown is as follows: When the car is in motion and it is desired to stop it, the lever 12 is thrown in the direction oppositeto that of the motion of the car, when the cams 8 will be turned through IOO IIO

the action of the connecting-links 11 and 10 until their peripheries 35 come into frictional contact with the rails. The friction between the cams 8 and the rails tends to rotate said cams still farther until such rotation has ceased through the action of the buffers 38 or until the motion of the car has become sufficiently reduced or until the motion of the car has stopped. The form of a periphery of the cam 8 is such that as the cam rotates its tendency is to pry the car upwardly from the rails, and thus gradually increase the pressure between the cams 8 and the rails. The springs 23 alford a yielding connection between the lever 12 and the link 11, thus preventing undue strain upon the lever 12 in case the cam 8 continues to revolve after the clutch-pin 16 has been seated in one of the notches of the quadrants 14.

Since motion of the car is upon the shoes 29, the slots 31 are provided, so that said wear may be compensated for by outward adjustment of the shoes 29.

1t will be seen that numerous details of the device shown may be altered without departing from the spirit of my invention. I therefore do not confine myself to such details except as hereinafter limited in the claims.

Vhat 1 claim as my invention, and desire to secure by Letters Patent, is#

1. In a railroad-car brake, the combination of a car-body; a cam fulcrumed on said carbody on a horizontal axis; means for turning said cam on its axis; said cam being of suitable form to engage the rail beneath the car While the car is in motion and, through frictional contact with said rail, to turn on its axis and tend to lift saidcar; a suitable stop on the car-body for limiting the movement of said cam; said cam being provided with adjustable means adapted to compensate for wear on its bearing-face.

2. A brake-cam of the class described, coinprising a body part having secured thereto a pair of parallel plates; a removable shoe fitting between said plates and forming the bearing-face of said cam; a plurality of bolts for securing said shoe in position, said plates having therein a plurality of parallel slots for receiving said bolts, and permitting of adjustment of said shoe relatively to said plates; and a removable backing-piece for fixing the position of said shoe.

3. In a railroad-car brake, the combination of a car-body; a transverse horizontal shaft journaled on said car-body; a cam secured to said shaft, said cam being of suitable form to be thrown into or out of engagement with the rail below the car by the turning of said shaft; a lever fulcrumed on said car-body; means for locking said lever into a plurality of different positions; and suitable connection between said cam and said lever whereby the turning of said lever will operate said cam, said connection being adapted to yield to permit said cam to continue to turn after said lever has been locked in a iixed position.

4. In a railroad-'car brake, the combination of a car-body; a transverse horizontal shaft journaled on said car-body; a cam secured to said shaft, said cam being of suitable form to be thrown into or out of engagement with the rail below the car by the turning of said shaft; a lever fulcrumed on said car-body; means for locking said lever into a plurality of different positions; an arm secured to said shaft; a link pivoted to said arm; and a pair of oppositely -disposed springs connecting said lever with said link, whereby the movement of the lever is communicated\to said cam; said springs being adapted to yield when said cam continues to move through contact with the rail after said lever has been locked in a fixed position.

Signed at Chicago this 20th day of July,

GEORGE GREMM. Witnesses:

WM. R. RUMMLER, RUDoW RUMMLER. 

